Trim Sender Limit Kit – Fits MerCruiser Alpha One Gen 2 & Bravo Stern Drives (Replaces 805320A03, 805320A1)

Trim Sender Limit Kit – Fits MerCruiser Alpha One Gen 2 & Bravo Stern Drives

This trim sender and limit switch kit is designed for a wide range of Mercury MerCruiser stern drives, including MC-I, R, MR, Alpha One, Alpha One Gen II, and Bravo I, II, & III models. It provides a complete replacement for both the trim position sender and the trim limit switch assemblies, ensuring your trim system functions accurately.

This assembly is a direct replacement for Mercury / MerCruiser part numbers 805320A03, 805320A1, 17693A2, 63115A12, 88678A4, and 88678A5. It also replaces aftermarket parts such as Sierra 18-7633 and Red Rhino MR-971.

• Complete Kit: Includes both the port side trim limit switch and the starboard side trim position sender.
• Ready to Install: Features wire leads with pre-installed electrical connectors for a direct fit.
• Critical Note: Designed for use with analog gauge systems only. Not compatible with SmartCraft digital systems.

Part Number Cross-Reference

Use this table to confirm equivalent part numbers across OEM and aftermarket brands.

Compatible Engine Models

Confirm your engine model/year in the table below. For Mercury owners, here’s a guide to help you identify your engine’s serial/model: Mercury Serial Number Guide. You can also review exploded diagrams to verify part numbers: Mercury Parts Diagrams & Catalog.

Technical Specifications

Package Contents

• 1 x Trim Limit Switch (Port Side)
• 1 x Trim Position Sender (Starboard Side)
• 2 x Wire Leads with Pre-installed Connectors

Installation Guide

1. Safety First: Disconnect the boat's battery before beginning any electrical work.
2. Access Components: Tilt the stern drive to the full "up" position to access the trim sender and limit switch located on the gimbal housing.
3. Disconnect Wires: Carefully unplug the electrical connectors for the old sender and limit switch.
4. Remove Old Switches: Unscrew and remove the old trim limit switch (port side) and trim position sender (starboard side). Note the orientation of the actuator arms.
5. Install New Switches: Mount the new trim limit switch on the port side and the new trim position sender on the starboard side, ensuring they are correctly seated.
6. Secure and Connect: Fasten the new components with the original hardware and connect the pre-installed wire leads to the boat's harness.
7. Test Operation: Reconnect the battery. Test the trim functionality and verify the trim gauge reads correctly and the upper limit switch functions.
8. Final Check: Ensure all connections are secure and wires are routed away from any moving parts.

Troubleshooting & FAQ

Q: How do I know if this kit will fit my MerCruiser drive?

A: This kit is designed for a broad range of MerCruiser drives, including MC-I, R, MR, Alpha One, Alpha One Gen II, and Bravo I, II, & III models. The best way to confirm is to match your original part number to those listed in our cross-reference table, such as 805320A03 or 805320A1.

Q: Will this trim sender kit work with my SmartCraft digital gauges?

A: No. This kit is specifically designed for systems with traditional analog trim position gauges. It is not compatible with MerCruiser's SmartCraft digital information systems.

Q: What are the signs that my trim sender or limit switch is failing?

A: Common symptoms include an inaccurate or non-functional trim gauge, the stern drive trimming up or down on its own, or the trim motor not stopping when it reaches the upper limit. These issues can be caused by a faulty sender (gauge issues) or a faulty limit switch (trim range issues).

Q: Which side of the gimbal housing does each part install on?

A: The kit is side-specific for proper operation. The trim limit switch must be installed on the port (left) side, and the trim position sender must be installed on the starboard (right) side.

Q: OEM vs. Aftermarket?

A: This listing is an aftermarket replacement part (not an OEM component). We build to OEM specifications using comparable-grade materials. Production is done in an ISO9002-certified facility, and each batch is inspected for consistent performance.

Q: How fast do you ship and how much does it cost?

A: We offer fast global shipping—typically 5–15 days worldwide—and standard shipping is free. Expedited options are available at checkout depending on your location.

Q: What is your warranty and return policy?

A: This product includes a 1-year warranty against manufacturing defects under normal use. If something goes wrong, contact our support team with your order details. Returns are accepted within our standard return window (unused & in original condition); please see our policy page or reach out for instructions.

Important Notes

• Verify that the product images and specifications match your original part. If discrepancies exist—even if your model is listed—do not proceed with the purchase.
• This product is an aftermarket replacement part and is not an OEM component.
• Professional installation is recommended to ensure safety and optimal performance.

Why Choose JLM MARINE?

• Quality Assured: As a trusted manufacturer for over 20 years, we supply top marine brands globally.
• Fast Global Shipping: Free delivery worldwide in 5–15 days.
• Direct from Manufacturer: Competitive pricing without compromising quality.